Light controlling apparatus



Sept 10, 1935. E L, COLE $014,039

LIGHT CONTROLLING APPARATUS Filed May 5, 1954 2 Sheets-Sheet l FIELS- INVENTOR fan/A20 L. COLE ATTORNEY Sept 1%, 1935. E. 1.. COLE 2,014,039

LIGHT CONTROLLING APPARATUS Filed May 5, 1954 2 Sheets-Sheet 2 INVENTOR EDWARD L". C LE ATTORNEY Patented Sept. 10, 1935 UITED STATES PAET OFFICE LIGHT CONTROLLING APPARATUS Application May 5, 1934, Serial No. 724,087

1 Claim.

My present invention relates to the art of il lumination, and more particularly to devices for controlling light rays emanating from a light source.

An object of this invention is to provide im proved type of construction of light projector of the general class indicated whereby a high degree of illuminating efficiency is attained through the expedient of a plurality of condensing lenses placed at predetermined locations about a suitable light source, each of which is adapted to gather a group of the rays diverging from the source and to refract them into more nearly parallel paths. Then by the correct positioning of suitable reflecting means in relation to each of the beams of light so developed, they all can be directed in a common direction or in other predetermined relationship to each other, far more accurately and with much less loss of dispersed light energy than can be attained in devices which do not provide for the collection of the divergent rays into more nearly parallel paths prior to their impingement against a reflector.

A more detailed object is to provide a light controlling device as above described embodying improved constructional details whereby is attained a device which will be relatively simple and inexpensive to construct, capable of facile and economical installation, which requires prac-.

tically no servicing whatsoever after having been installed, and which, by reason of its high efliciency in controlling the direction of emanation of rays from the light source, can be relied upon to attain a given degree of illumination at an absolute minimum of cost by making it possible to use a light source of lower power than would otherwise be necessary to attain the same degree of illumination.

The invention possesses other objects and advantageous features, some of which, with those enumerated, will be set forth in the following description of the inventions particular embodiments which are illustrated in the drawings acoompanying and forming a part of the specification. The forms of construction herein disclosed have proven in actual use to be highly eflicient in operation, economical in construction, installation, and operation, and'generally desirable in other respects. For these reasons, the details herein described may be considered as preferred. It should be mentioned, however, that while these details are specifically described hereinafter, they are to be considered merely as exemplary, and that variation of the described forms may be elfected within the scope of the appended claim without departing from the essence of the invention.

Referring to the drawings:

Figure 1 is a longitudinal, vertical, medial sec- 5 tional view of a light-controlling device embodying the principles of the present invention.

Fig. 2 is a diagrammatic View of the apparatus illustrated in Fig. 1, showing it adjusted differently to produce a different lighting effect.

Fig. 3 is a view similar to Fig. l, but showing a modified construction of illuminator. The plane of section can be considered as having been tak n upon the line 33 of Fig. l with the direction of view as indicated by the arrows.

Fig. 4 is a View looking into the open end of the illuminator of Fig. 3, the direction of View eing indicated by the arrow 4.

Fig. 5 is another view similar to Fig. 1, showing 20 another modification of my illuminator.

Fig. 6 is another view similar to Fig. l, illustrating still another modified form. This figure can be considered as a sectional View taken upon the line 66 of Fig. 8.

Fig. '7 is a diagrammatic view of the apparatus shown in Fig. 6. Here again the illuminator is adjusted dififerently to obtain illumination of a different character.

Fig. 8 is a View looking into the open end of the device illustrated in Fig. 6, the direction of View being indicated by the arrow 8.

One form of my improved light projecting apparatus is shown in Figures 1 and 2, which illustrate the light controlling device it as comprising a substantially tubular lamp housing ll, within which any suitable source of light, such as an incandescent bulb I2 is disposed, and a shade it, the inner surface of which is made highly reflective, either by applying silvering, chrome plating, or the like directly to the inner surface of the shade I3, or by mounting mirrors i4 thereupon. Preferably the lamp housing I! is composed of two parts It and I! rigidly secured together as by rivets E8. The outer part it accommodates the socket 9 for the lamp l2, which is mounted within the housing H for adjustment longitudinally thereof through the expedient of an elongated nipple 2! having a running thread engaging with and extending through the hub 22 of a spider 23 which is rigidly secured to the outer end of the outer part l6 of the lamp housing H as by rivets 24. Preferably the conductors 26 whereby the lamp I2 is energized lead 5 to the socket l9 through the nipple 2| which may be of tubular form for their accommodation.

The inner part I! of the lamp housing H is provided with a plurality of condensing lenses 3|, 32, one of which is mounted in the end wall 33 preferably in such position that the axis of the lens coincides with the longitudinal axis of the lamp housing Hence, the front lens 3| serves to intercept rays 34 diverging outwards from the filament 36 of the lamp i2 and refract them substantially into parallelism with each other, i. e., into a condensed beam such as indicated at 31, which is projected from the illuminating device in a direction straight forwards with respect thereto.

The other lenses 32 are mounted in the side walls 4| of the inner or forward part I! of the lamp housing surrounding the lamp H3 at the sides thereof.

Preferably the parts are so proportioned and arranged that the focuses 42 of all of the lenses 3| and 32 lie substantially at a common point within the housing so that the lamp |2 can be positioned with its filament 36 accurately at the focuses of all the lenses and thereby derive the most nearly completely condensed beams to be projected by each lens, including the side lenses 32 as well as the front lens 3|.

In the modification illustrated in Figures 1 and 2, the plane of each of the side lenses is substantially perpendicular to that of the front lens 3|, the result being that when the lamp i2 is placed in its position of most accurate focus, i. e., with its filament at the focuses of all the lenses 3| and 32, the beams 43 projected by the several side lenses 32 radiate outwards in divergent directions from the housing i i, but each of them being substantially perpendicular to the beam 3! from the front lens 3|.

For each of the side lenses 32, a fiat reflecting surface is provided, in the present modification a mirror I4 being secured to the inner surface of the shade I3 opposite each of the side lenses 32. The angle between the plane of each mirror l4 and the longitudinal axis of the illuminating device is preferably slightly less than 45, with the result that when the lamp I2 is positioned accurately with its filament at the focuses of the lenses, the beams 65 reflected by the mirrors l4 converge slightly toward each other and toward the beam 31 from the front lens 3|, this condition being exaggerated in Fig. 1. In this manner a relatively large amount of light energy can be concentrated on a given spot at a considerable distance from the illuminator, this distance depending upon the angular ty of the mirrors with respect to the axis of the device. However, a less concentrated light can be projected onto a larger field by adjustment of the socket Hi to move the lamp l2 toward or away from the front lens 3|, this being accomplished by rotating the nipple 2| with respect to the spider 23 as will be readily understood. Obviously, such movement of the lamp l2 displaces the filament 36 from the focus 42 of the front lens, the result being that the ray 3'? will spread more and over a larger field with a less concentrated light, as illustrated in Figure 2. However, the distance between the filament and each of the side lenses 32 is not varied greatly, because the lamp moves substantially in parallelism with the planes of these lenses. Hence, the beams will not be thrown out of focus nearly as much as will the beam 31'; they will, however, be projected toward their several mirrors I4 at different angularity therewith, and the beams 46 reflected by the mirrors will have altered directions. For example, if the lamp be moved closer to the front lens 3|, as in Figure 2, the angle between each beam and its mirror M will be increased, and since the angle of reflection of light is always equal to the angle of incidence, the angle between the mirror and the reflected beam also will be increased, thus causing the beams 33 to cross each other and the central beam 3'! before they reach the distance from the projector at which they previously converged. Hence, if the field be the same distance from the illuminator as before alteration of the adjustment, a larger field will be illuminated by the central beam 3?, and surrounding this field, and/or disposed inside this field adjacent the periphery thereof will be a circle of areas illuminated by the beams It should be explained, however, that instead of each of these areas being clearly defined and distinct from each other, they all tend to merge with each other and with the area illuminated by the central beam 3?, and thus produce a flood of relatively evenly distributed but less intense light over an area larger than that illuminated by the device when accurately focused.

Substantially the same ultimate result is obtained if the lamp 522 be moved further from the front lens i, the principal difference being, however, that instead of converging and crossing, before they reach the field to be illuminated the beams 45 will diverge slightly.

Lock nuts on the nipple outside the lamp housing ii provide simple means for releasably fastening the parts in adjusted position.

At least one of the lenses, preferably the front lens Si, is removable to permit inspection, replacement, and/or repairs of the light source. With this end in view, the means for attaching the lens preferably comprises a bezel 52 releasably retained in place by screws 53 or their equivalent. However, as the figures clearly indicate, the entire lamp housing l is substantially tightly closed with the exception of the aperture through which the nipple 2| extends, this aperture preferably being sufiiciently larger than the nipple to permit ventilation of the interior of the housing so as to assist in dispersion of the heat given off from the light source. The tight closing of the housing is of importance from the standpoint of exclusion of dust, which otherwise would tend to collect upon the surface of the bulb l2 and the inner surfaces of the condensing lenses 3| and 32 and thus tend to impair the efficiency of light projection.

Whereas the modification thus far described includes four (4) side lenses 32 and consequently is provided with four mirrors hi the shade I3 is square in cross section, as is also the lamp housing However, Figures 3 and 4 illustrate a modified form of illuminator which employs a five-sided lamp housing 8|, each side carrying a side lens 32 in addition to the front lens 53. There being a separate, fiat mirror 64 for each of the side lenses 52, the shade 66 also is of pentagonal cross section.

Figure 5 illustrates a modification wherein the side lenses instead of being positioned with their respective planes perpendicular to that of the front lens 12, are disposed further from the front of the lamp housing 13 as compared with the constructions previously described. Hence, in order to place them normal to lines radiating from the filament of the bulb 11, they are disposed in sloping position, as clearly shown in the figure.

Figures 6, 7 and 8 illustrate a still further modified form wherein instead of surrounding the lamp 88 with a plurality of circular condensing lenses as in the previously described forms, a single, annular lens 82 is employed, with the lamp 3! disposed at the center of the annulus, i. e., the ring-shaped lens surrounds the lamp, as the figures show. The inner surface 83 of the lens is flat, considered axially of the annulus, and the outer surface 84 is arcuate, or convex, so that in cross section taken along the axis of the annulus, each side of the lens has the appearance of a plano-convex lens. The lens 82 may be formed. with its inner surface 83 cylindrical, or frusto-conical with its smaller end forwards (as illustrated), or frusto-conical with its larger end forwards, thus making this modification correspond respectively to those shown in Figures 1 and 2, Figures 3 or 4, or in Figure 5, it being understood that the angularity of the reflector will be selected to meet the requirements of the type of lens used.

When the annular condensing lens 82 is employed, instead of condensing light from the lamp 8! into a plurality of beams which radiate in several directions from the lamp housing, a circular sheet of light 86 is formed, and accordingly a frusto-conical shade i3? and reflector 88 (which in this case can most conveniently be provided by coating the inner surface of the shade Bl with suitable highly reflective material) should be used. The circular sheet 86 of light is reflected by the reflector 88 into a cone 89 of light which tapers substantially to a point where it merges with the beam ill from the front lens 92, or it spreads outwards therefrom to illuminate a larger area, depending upon the adjustm'ent of the lamp 8| within the lamp housing 93. Here again, however, instead of being clearly defined from the central beam at and this forming a ring of illumination surrounding the spot illuminated thereby, both the beam 9! and the cone 89 are found to be sufiiciently diffused to merge with each other and thus present what otherwise would be classed as spotty illumination.

I claim:

In a light projector, a lamp housing comprising an inner part and an oumr part, said parts being of substantially tubular construction and one being an extension or" the other, a shade flarng from the juncture of said inner and outer parts, means common to said inner and outer parts and to said shade for rigidly securing them together, means mounted in said outer part and adjustable axially of said housing for supporting a source of light, a light source mounted in said supporting means with its luminous portion disposed within said inner part, said light source being substantially completely enclosed within said housing, lens means in the side Walls of said inner part and encircling said light source for retracting rays diverging toward the front and rear of said projector substantially into parallel planes to which the axis of said projector is perpendicular, reflector means carried by said shade for reflecting said refracted rays forwards from said projector, and a lens in the inner end of said inner part of said housing for retracting rays diverging forwards from said source into predetermined relation with said reflected rays.

EDWARD L. COLE. 

